Network upgrade from 2012R2

[BJG]

Most of the network here including the DCs is still based on 2012R2, so I just wanted a quick reality check on the best way to move forward...

 

1) The plan was to move to 2019. Is that still sensible or should we be looking at 2022...? I'm thinking 2019 might be a sensible intermediate step in any case...?

2) Can I move the domain from 2012R2 to 2019 via in-place upgrades or would it be more sensible to introduce a new 2019 server, at least initially...?

[mavhc]

If they're VMs with a lot of config, make a snapshot and upgrade, via 2016. Always buy the latest version of Server, then you can install any older version. I stopped at 2019 but will go to 2022 in the holidays probably. Not that SIMS technical roadmap even acknowledges 2022 exists.

[BJG]

...really...? Via 2016..? OK, thanks! I'm thinking especially of the DCs; I've heard bad things can happen if you try reverting to snapshots on those.

 

https://www.itprotoday.com/server-virtualization/never-snapshot-domain-controller-here-s-why

Edited July 24, 2023 by BJG

[howartp]

2012 R2 will go straight to 2019 no problem.

 

2012 will need to go via 2016.

 

I did several last summer straight to 2019, though there weren't any DCs to do.

[mavhc]

Oh yeah, only needed 2016 for R1, not R2. So stupid.

 

Disconnect from network, snapshot, upgrade. If upgrade fails revert. If upgrade is ok reconnect to network.

[FN-GM]

It’s not advised to snapshot 2012 R2 domain controllers. It isn’t supported.

 

Personally I would build a second DC, run it side by side with your existing DC, migrate the roles and decommission the old. It’s more controlled and less risky.

 

I would go right to 2022. You can’t increase the first function level beyond 2016, but you will get extra support lifecycle.

 

Also get cracking. There is hardly any time left on server 2012.

[BJG]

OK! Got a plan now. Thanks for the info.

[Olliedawg]

I’ve got a similar job, inherited network which has a few 2012R2 vm’s still. (3 DC’s, couple of other VM’s..) Can you go straight from 2012R2 to 2022? (Apart from the DC’s, will be looking to rebuild these).

 

Also had to move AAD connect to a 2016 VM today from one of our DC’s, as support for the 1.x versions are being depreciated in October, and will no longer sync objects to azure

[lornebooker]

We went from 2012 to 2022 no problems, for SIMS, just an in-place upgrade.

[Jcx500]

Spin a new dc up , transfer roles etc. decom old dc leave it on for a few weeks in case of any fallout. Then turn server off

[mavhc]

There's no problem upgrading DCs as well, depends what's installed on them, obviously the best solution is to have everything scripted so you just press Go and it installs a new VM, configures it, and don't have to manually make any changes, but depends what scale you're running at.